Whistle-Blower’s Complaint Is Said to Involve Multiple Acts by Trump

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So Nunez mentioned the letter that Dems sent to Ukraine during the Mueller investigation. Not sure if it has been posted on here, but here it is.

https://www.foreign.senate.gov/imo/media/doc/5-4-18%20Menendez%20joint%20letter%20to%20General%20Prosecutor%20of%20Ukraine%20on%20Mueller%20investigation.pdf

I guess my question is....these are senior Senators whom Trump is obviously their political foe. They re NOT part of Mueller' team. They hold influence in appropriating money to Ukraine. Is this proper and aren't they implying how to investigate with a quid pro quo.